Wednesday, November 23, 2011

Siri's strange phonotactics

Colin Wilson recently gave a talk here at Penn about why speakers don't necessarily say words in a foreign language the way foreign language speakers do. For example, the capital of Georgia (the country) is Tbilisi, which an initial [tb] onset cluster. Here, listen to pronunciation on Wikipedia: Tbilisi, then say it back out loud. That's basically the experiment Colin was talking about.

So, I'm guessing that if you didn't manage to say Tbilisi exactly like the recording did, you probably said something like [tɨbilisi], adding in an extra vowel between the [t] and [b]. There are a few different explanations for why you might have added in that extra sound.

You hallucinated, and thought you heard [tɨbilisi].

You accurately heard [tbilisi], but then when you tried to say it, it came out [tɨbilisi].

Colin is pursuing another kind of analysis, where the way a Georgian speaker says /tbilisi/ sounds more like the way you would say /tɨbilisi/ in English, than the way you would say /tbilisi/ in English (if you were ever to say such a thing).

It's pretty cool stuff, and strangely reminded me of a similar repetition experiment I inadvertently performed with my iPhone. Here's a video re-enactment:

How weird is that! Siri heard me say [ʃəvan], but for some reason repeated it back [sajobən]!

Ok, I guess I really know what's going on here, and it's not phonotactics, but it's fun to pretend. Clearly, the transcription with the highest probability given my speech was the Irish spelling "Siobhan": P(transcription | audio). But, given the text, the text to speech (P(audio | transcription)) produces [sajobən].

It still strikes me weird that Siri has some kind of dictionary lookup to give me "Siobhan" for [ʃəvan], but then does a procedural text-to-speech.

P.S. I think that I have an intrusive /l/ after "how" the second time I say "How do you spell Siobhan?".